Method for Producing a Diffractive Optical Element and Diffractive Optical Element

Abstract

A method for producing a diffractive optical element and a diffractive optical element are disclosed. In an embodiment a method for producing a diffractive optical element includes generating a surface structure by implanting ions into a material of a substrate, a layer or a layer system, wherein the surface structure includes a structure height of less than 10 nm.

1 .- 15 . (canceled) 
     
     
         16 . A method for producing a diffractive optical element, the method comprising:
 generating a surface structure by implanting ions into a material of a substrate, a layer or a layer system, wherein the surface structure comprises a structure height of less than 10 nm.   
     
     
         17 . The method according to  claim 16 , wherein the surface structure is generated with the structure height varying in lateral direction. 
     
     
         18 . The method according to  claim 16 , wherein implanting ions comprises implanting ions through a patterned mask layer. 
     
     
         19 . The method according to  claim 16 , wherein implanting ions comprises implanting ions by a laterally confined ion beam, and wherein a ion fluence of an ion beam is varied during the ion implantation. 
     
     
         20 . The method according to  claim 16 , wherein the ions are implanted to an implantation depth between 10 nm and 500 nm, inclusive. 
     
     
         21 . The method according to  claim 16 , wherein an ion energy during the ion implantation is between 2 keV and 100 keV. 
     
     
         22 . The method according to  claim 16 , wherein the structure height of the surface structure is a non-integer multiple of a lattice plane spacing of the material or a non-integer multiple of a thickness of a single layer of the layer system of the diffractive optical element. 
     
     
         23 . The method according to  claim 16 , wherein the structure height of the surface structure is smaller than a grating plane spacing of the material at the surface or is smaller than a thickness of a single layer of the layer system of the diffractive optical element. 
     
     
         24 . A diffractive optical element comprising:
 a surface structure in a material of a substrate, a layer or a layer system,   wherein the surface structure comprises a laterally varying structure height of less than 10 nm, and   wherein the substrate, the layer or the layer system comprises an ion implantation region below the surface structure.   
     
     
         25 . The diffractive optical element according to  claim 24 , wherein the diffractive optical element is a reflection diffraction grating. 
     
     
         26 . The diffractive optical element according to  claim 24 , wherein a ion implantation depth is between 10 nm and 500 nm, inclusive. 
     
     
         27 . The diffractive optical element according to  claim 24 , wherein the structure height of the surface structure is a non-integer multiple of a lattice plane spacing of the material at the surface or a non-integer multiple of a thickness of a single layer of the layer system of the diffractive optical element. 
     
     
         28 . The diffractive optical element according to  claim 24 , wherein the structure height of the surface structure is less than a grating plane spacing of the substrate or is less than a thickness of a single layer of the layer system. 
     
     
         29 . The diffractive optical element according to  claim 24 , wherein the substrate is a single crystal or an amorphous substrate. 
     
     
         30 . The diffractive optical element according to  claim 24 , wherein the layer or the layer system is a mirror for EUV radiation or X-rays.